Pass Over the Peanut Oil

Why, in the United States, at Pesach, is it OK to cook with peanut oil, but not to eat peanuts?
We've tried unsuccessfully to get an answer to this question
for at least 25 years. Now, having harnessed the power of the
Internet, we eagerly await your response.

David Kaplan wrote:

Shalom, I have a question which as you can see concerns the 'laws' and traditions governing
what one may eat during Passover. I cannot understand why Sephardic
Jews are allowed to eat beans, legumes and rice on Passover and
Ashkenazic Jews are not. This is not the same as eating pork
or milk and meat obviously. I really find this a difficult issue
to come to terms with. Please help. Thanking you in anticipation.

Dear Carol and Barry Stein & David Kaplan,

Kitniot is the Hebrew word for all types of legumes, such as peanuts, peas and beans,
and cereal grasses such as rice and corn.

According to the Torah, kitniot are permitted on Passover because kitniot are not considered
chametz (leaven).

But kitniot are similar to chametz in that they swell when water is added, and
people often use them as a flour substitute. Furthermore, kitniot
are often stored together with grain, and sometimes a bit of grain
gets mixed into the kitniot. For these reasons, Ashkenazic
Jews throughout the centuries have adopted the practice to refrain
from kitniot during Passover.

Sephardic Jews, however, never adopted this practice. Therefore, they are allowed to eat kitniot,
provided they check it to make sure there's no wheat mixed in.
(For this reason, some Sephardic Jews also have the custom to
refrain from rice, although they eat other types of kitniot.)

Now about peanut oil. Oil derived from kitniot no longer resembles chametz
because it no longer swells when you add water. Rabbi Tzvi Pesach
Frank, zatzal, a former Chief Rabbi of Jerusalem, cites
an opinion that kitniot derivatives are therefore permitted.
Many people in the United States follow this ruling and use kitniot-based
oil on Passover. Many are strict, however, and use olive or walnut oil.
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